Toothbrush

ABSTRACT

A toothbrush comprises a handle and a head for improved cleaning to the interdental regions of the teeth, said head comprising a linear arrangement of bristles transverse to the general longitudinal axis of the brush and extending along a length equal to or greater than a third of the width of the toothbrush head at the location of the arrangement, characterised in that a portion of the bristles at either end of the arrangement are angled away from the vertical such that the arrangement presents a fan-shaped transverse brushing array.

BACKGROUND AND SUMMARY

[0001] 1. Field of the Invention

[0002] The present invention relates to a toothbrush comprising a handleand a head for improved cleaning to the interdental regions of theteeth, said head comprising a linear arrangement of bristles transverseto the general longitudinal axis of the brush and extending along alength equal to or greater than a third of the width of the toothbrushhead at the location of the arrangement.

[0003] 2. The Related Art

[0004] U.S. Pat. No. 1,191,556 (Blake) details a toothbrush consistingof the usual tuft bristle formation interspersed with flexible blades.

[0005] WO 99/01054 outlines a toothbrush with flexible fin structuresthat aid in the cleaning process by penetrating the interproximal regionof teeth.

[0006] U.S. Pat. No. 5,392,483 details a patent application with normalbristle tufts in which the terminal tufts of the toothbrush are inclinedaway from each other.

[0007] U.S. Pat. No. 3,295,156 discloses individual tufts fan but not aconfluent linear array of bristles.

SUMMARY OF THE INVENTION

[0008] According to the present invention, there is provided atoothbrush comprising a handle and a head for improved cleaning to theinterdental regions of the teeth, said head comprising a lineararrangement of bristles transverse to the general longitudinal axis ofthe brush and extending along a length equal to or greater than a thirdof the width of the toothbrush head at the location of the arrangement,characterised in that a portion of the bristles at either end of thearrangement are angled away from the vertical such that the arrangementpresents a fan-shaped transverse brushing array.

DETAILED DESCRIPTION OF INVENTION

[0009] Preferably the linear arrangement presents a fan-shaped brushingarray which is comprised of a row of individually fixed bristle tufts.

[0010] The bristle tufts making up the fan-shaped brushing array maysuitably be fixed to the brush head by so called anchor technologywhereby the bristle tufts are bent in half by a strip of metal which ispressed into the wall surrounding the tuft hole.

[0011] Alternatively the tufts may be fixed to the brush head byin-mould welding. This is a newer technique which involves the mouldingof the brush head around a fixed bristle tuft.

[0012] The bristle tuft holes used to fix the bristle tufts to the headare suitably dimensioned to provide for the formation of a fan-shapedbrushing array. Preferably, this means that the tuft holes are locatedclose to one another and in a linear arrangement. More preferably, thebristle tuft holes are square or rectangular in shape. Where they arerectangular they consist of a pair of opposing long wall faces and apair of opposing short wall faces with the array of holes arranged suchthat the long wall faces are substantially aligned. Preferably the longfaces are greater in length than the short faces, more preferably, thelong faces are from about 1.01 to about 1.2 times the length of theshort faces. Preferably, the short faces are aligned with the generallongitudinal axis of the brush head. In this way the confluence of theindividual bristle tufts in the fan-shaped brushing arrays can bemaximised.

[0013] In a more preferred embodiment the holes at the two edges of thetransverse linear arrangement when viewed from above are tapered suchthat the edge of the fan presents a softened wall. This reduces the hardnature of bristle tufts which protrude beyond the normal brushingsurface.

[0014] The linear arrangement brushing elements according to theinvention are fan-shaped. This means that viewed from the tip end of thebrush down towards the handle the transverse array presents a wall ofbristle tufts which is narrower at the bottom than at the top, i.e. thebristle brushing area is greater than the area of the tufts holes andextends laterally beyond the end holes.

[0015] Preferably, a portion of the bristles within the fan-shapedbrushing array are angled with respect to the vertical. Preferably,these bristles area angled away from the centre line along thelongitudinal axis of the brush head. Preferably, the fan-shaped brushingarray is dimensioned such that the ends of the fan-shaped array areangled at from about 0.5° to about 30° from one another, more preferablyfrom about 5° to about 25° and especially from about 13° to about 22°.

[0016] In a preferred embodiment the bristles at the ends of the lineararrangement which are angled comprise a portion amounting to from about0.5 to about 30% of the bristles within the linear fan-shaped array.More preferably, from about 3 to about 25% and especially from about 10to about 20% of the bristles in the fan-shaped linear arrangement areangled.

[0017] In another preferred embodiment the brushing surface of thefan-shaped array is arcuate when viewed from the tip of the brush downtowards the handle. Preferably, the brushing surface of the fan-shapedarray is arcuate in the sense that it extends further from the brushhead in the middle of the array and gradually less so at the ends.

[0018] In a preferred embodiment the brush according to the inventioncomprises further bristles which may or may not be arranged in bristletufts as is the usual fashion in toothbrush technology. These‘conventional’ bristles provide additional cleaning to the teeth in use.Typically these conventional bristles extend an average length l fromthe brush head to a tip. Preferably, the bristles making up thefan-shaped array extend a length ranging from about 1 to about 1.5 l,more preferably from about 1.05 to about 1.4 l and especially preferablyfrom about 1.1 to about 1.35 l. This relationship between the lengths ofthe bristles in the fan-shaped array and other, conventional bristles onthe brush head provides a synergistic cleaning of the teeth during use.The fan-shaped arrays excise the debris from the interdental regions andthe conventional bristles remove the debris from the dentition such thatit can be removed from the oral cavity during expectoration.

[0019] In a further preferred embodiment the bristles in the fan-shapedarray are more flexible than those in the conventional tufts. Thisflexibility is not just due to the longer length but also because of themore flexible nature of the materials used. It may also be due to thereduced diameter of the bristle filaments in the fan-shaped array.Preferably the diameter of the bristle in the fan-shaped array rangesfrom about 0.75 to about 0.99 that of the bristles in the conventionalbristles, more preferably from about 0.85 to about 0.95 and especiallypreferably from about 0.9 to about 0.95 that of the conventionalbristles.

[0020] In a further preferred embodiment the fan-shaped array issupported on the brush head by a supporting boot. Such supporting bootsare known in the prior art, for example in EP 0 888 072 (M+C Schiffer).

[0021] In a preferred embodiment such supporting boots compress thefan-shaped arrays such that the bristle tufts present a moreconcentrated brushing surface without compromising the fan-shapedarrangement. More preferably, the compression occurs in an axis alignedto the general longitudinal axis of the brush head. In the alternativethe compression may also occur in a direction substantially transversethe general longitudinal axis of the brush head. In this way thecompression slightly reduces the angle of the angled bristles at theedges of the fan-shaped array but this also assist in concentrating thebristles at their brushing ends.

[0022] In a more preferred embodiment the boots have an end on profilesubstantially similar to the profile of the fan-shaped array also in endon view. In other words it is preferred that the profile of the boots isalso arcuate being higher in the middle than at the edges.

[0023] It is also preferred that each individual boot encompasses anentire fan-shaped array so that the fan shaped array does not lose itsconfluent bristle presentation.

[0024] The boots are typically moulded out of an elastomeric materialwhich provides some elasticity to the supporting role of the boot.Suitable elastomers are well known in the art to the person skilled inplastics manufacture.

[0025] In an alternatively preferred embodiment the brush according tothe invention comprises a rubbery tooth pick device for cleaning furtherthe interdental regions of the teeth. While tooth picks are known inbrushes they are not known in combination with the fan-shaped bristlearrays as defined herein. We have surprisingly found that the cleaningefficacy of the toothpicks is markedly improved with the combination ofpicks and fan-shaped arrays since the fan-shaped arrays loosen the hardto remove material stuck between the teeth and the picks are then ableto remove said matter more easily.

[0026] Preferably, said pick is a flattened structure with flattenedfaces lying transverse the general longitudinal axis of the brush head.Accordingly, the pick is thus substantially bendable in a direction ofmotion along the general longitudinal axis of the brush head and less soin a direction transverse the general longitudinal axis of the brushhead. This means that the pick has less resilience and thus greatercleaning efficacy when bent in a direction transverse the longitudinalaxis of the brush head than when bent in a direction along said axis.This allows the picks to get between the teeth and prise out the hard toremove material when the brushing direction is up and down (in adirection transverse the general longitudinal axis of the brush head)rather than side to side. In a side to side motion the pick provides atooth polishing effect as it rubs over the surface of the tooth.

[0027] In a preferred embodiment the pick is ellipsoidal in shapetowards the tip end of the pick. Said ellipsoidal shape provides themaximum cleaning efficacy without harming the gums. A pointed shapewould harm the gums and a fully rounded shape would not be able to focusthe pressure in the tip sufficiently to remove fastened debris frombetween the teeth.

[0028] Said picks are suitably made from an elastomeric material similarto the material of the boots and these are commercially available inmany different forms which are well known to the man skilled in the art.Accordingly, the behaviour of the picks can be modified by the manskilled in the art by careful consideration of the physical propertiesof the elastomeric materials.

[0029] The foregoing description and examples illustrate selectedembodiments of the present invention. In light thereof variations andmodifications will be suggested to one skilled in the art, all of whichare within the spirit and purview of this invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Further objects, features and advantages of the present inventionwill become more evident through consideration of the following drawingsin which:

[0031]FIG. 1 is a side elevational view of part of a brush headaccording to the invention;

[0032]FIG. 2 is an end on view of the same brush head;

[0033]FIG. 3 is a side elevational view of part of a brush headaccording to the invention;

[0034]FIG. 4 is a perspective view of part of a brush head according tothe invention;

[0035]FIG. 5 is a plan view of part of a brush head according to theinvention;

[0036]FIG. 6 is a plan view of part of a brush head according to theinvention;

[0037]FIG. 7 shows part of a brush head in perspective view; and

[0038]FIG. 8 shows a brush head in elevational view.

DETAILED DESCRIPTION OF DRAWINGS

[0039] In more detail, FIG. 1 discloses a brush head (1) comprising afan-shaped brushing array (2). In this view the fan-shaped array (2)cannot be perceived as a fan-shaped array since it is transverselylocated on the brush head and is seen end on. The figure only shows thefan-shaped array and not any of the other features of the brush head forthe sake of clarity. Other features may also be present as describedherein without affecting the nature of the fan-shaped array.

[0040]FIG. 2 discloses the brush head according to FIG. 1. Shown is abrush head (1) and a fan-shaped array (2). The bristles at the edges ofthe fan-shaped array are angled away from the vertical by α°. Thebristles at the centre of the fan-shaped array are substantiallyvertical with respect to the brush head. Again, the figure only showsthe fan-shaped array and not any of the other features of the brush headfor the sake of clarity. Other features may also be present as describedherein without affecting the nature of the fan-shaped array.

[0041]FIG. 3 is a brush head comprising three fan-shaped arrays (2).Starting from the tip end of the brush head the first fan-shaped arrayis a distance a from the second fan-shaped array. The second array islocated at a distance b from the third array. Distance b is typicallyfrom 0.5 to 1.1 times a, preferably from 0.6 to 0.9 and especiallypreferably from 0.7 to 0.8 times a. These values are applicable in anyembodiment of the invention comprising three fan-shaped arrays. Onceagain the figure only shows the fan-shaped arrays for the sake ofclarity.

[0042]FIG. 4 is a perspective view of a brush according to theinvention. Shown is a fan-shaped array (2) which is supported by asupporting boot (4). Said boot extends from the brush head up to from 5to 30% of the full extent of the average bristle height in the array.Preferably, it extends to from 10 to 25% the height. These values beingapplicable for any brush according to the invention which comprisessupporting boots. Once again the figure only shows the fan-shaped arrayin a boot for the sake of clarity.

[0043]FIG. 5 shows a brush head comprising a row of tuft holes which arecapable of housing a fan-shaped array. Shown are four bristle tuft holes(5) which have a length c and a width d which define a rectangular

[0044]FIG. 6 shows a brush head similar to that in FIG. 5 but comprisinga pair of lateral tufts holes (6) which are tapered towards the edge ofthe brush head.

[0045]FIG. 7 discloses a brush head comprising a fan-shaped array (2)and a tooth cleaning pick (7). Said pick (7) is ellipsoidal in shape andflattened in a direction substantially along the general longitudinalaxis of the brush head.

[0046]FIG. 8 discloses an elevational view of a toothbrush according tothe invention. Shown are a brush head comprising three longitudinallyspaced fan-shaped arrays (2), three longitudinally spaced picks (7) andconventional bristle tufts (8) there between. The conventional bristletufts extend a length l from the brush head and the fan-shaped arraysextend a distance greater than l from the brush head. The picks arelocated between said fan-shaped arrays and the latter are disposedwithin supporting boots (4). The bristles making up the fan-shapedarrays do not extend longitudinally beyond the supporting boot'sperimeter contour.

What is claimed is:
 1. A toothbrush comprising a handle and a head forimproved cleaning to the interdental regions of the teeth, said headcomprising a linear arrangement of bristles transverse to the generallongitudinal axis of the brush and extending along a length equal to orgreater than a third of the width of the toothbrush head at the locationof the arrangement, characterised in that a portion of the bristles ateither end of the arrangement are angled away from the vertical suchthat the arrangement presents a fan-shaped transverse brushing array. 2.Toothbrush according to claim 1, wherein the linear arrangementcomprises a row of individually fixed bristle tufts.
 3. Toothbrushaccording to claim 1, wherein the portion of bristles at either end ofthe linear arrangement are angled at from about 0.50 to about 20°. 4.Toothbrush according to claim 1, wherein the angled portion of bristlesat either end of the linear arrangement constitutes from about 0.5% toabout 30% of the total number of bristles in the arrangement. 5.Toothbrush according to claim 1, wherein a brushing edge of the lineararrangement is arcuate.
 6. Toothbrush according to claim 1, wherein thelinear arrangement is supported by a supporting boot.
 7. Toothbrushaccording to claim 6, wherein the boot compresses the linear arrangementin a direction transverse the general axis of the linear arrangement. 8.Toothbrush according to claim 1, wherein the brush also comprisesrubbery picks.